Defoliating with oxidized white oil emulsions



WGLW-n a 4 2,945,753 Patented July 19, 1960 DEFOLIATING WirH oIZLED WHITE O EM nsroNs H No Drawing. Filed Dec. 21, 195-5, Ser. No. 554,395

10 Claims. c1. 7 1-2.7

This invention relates to improved compositions and methods for defoliating plants. More particularly it relates to improved aqueous emulsions for carrying out these purposes containing as'the active ingredient materials selected from the group consisting of oxidized white oils and their esters. V

The importance and desirability of defoliating living plants is well known. Of particular widespread economic importance is the defoliation of cotton, 'especially since the successful development of the mechanical cotton picker. This latter development has promoted much research and development in the field of artificial defoliation. Use of defoliants thus increases the efliciency of mechanical cotton pickers They permit farmers to harvest crops without waiting for frost to naturally defoliate the plant. 7

It has now been found that particular multi componentaqueous emulsions having as the activeingredients oxidized white oils or their esters areespeciallyeffective defoliants, These emulsions comprise in addition. to the active ingredients and wat'enaminer'al spray'oil and an oil soluble emulsifying'aglent'. All these four components in' combination are necessary to s'e'ourethe' desired defoliating effect without deleteriously'"affecting the remainder of the plant. The concentrations; as explained in further detail below, are extremely importan'ti'n this connection as e.g. lesser quantities of the active compounds do not; produce the desired results;

The active ingredients of this invention are prepared by non-catalytically oxidizing, .as. .by ,air or oxygen 'blow- .ing, an aromatic-free, petroleum white oil at atemperature in the range of 'aboiit'ISO t'o 190 C. for a time interval in the range of aboutQZ to 12 hours. The oil is thus oxidized to a peroxide number (milliequivalents of active oxygen per liter of oil) of 10 to 100, preferably 25 to 50, and an oxygen content of about 1 to 20 wt. percent, preferably to 15 wtwpercent; The-definition of peroxide number set forth above is described in The Chemical Constituentsof Petroleum, by A. N. Sachanen (1945 ed.), at page 332, footnote 89. It is to be understood that the t erm active ingredients as used herein connotes-the total white oil oxidized to the level indicated rather than .onlythe oxygenated materials. These latter are a complex mixture of alcohols, acids, aldehydes,

acetals, etc, and the efiicacy of the active ingredientis believed to be due to the interaction of -these materials, particularly the interaction on balance of acids and peroxides. The ranges stated are consequently: extremely importantin order to obtain the. desired results- The white oil starting material is consequently of importance also.

The white oils utilized are naphthenic, aromatic-free oils (U.S.P. petrolatum liquidum heavy) prepared by the well-known exhaustive sulfuric acid treatment of a heavy petroleumvdistillate to remove substantially all aromatics. The properties of the oil utilized have been found to Molecular weight 200-500 Specific gravity,60/60 F. "0.75-0.9 0 saybolt'visosity 100 F. 50-200 Unsulfonated residue "percent" 95-100 Pour115oih't' F 0 Petroleum fractions outside the range of this oil donot yield satisfactory results.

. Some typical white oils arez Marcol a U. S. P. light white mineral oil; and XCT white oil, the latter having the following properties:

Dish:

- I.B.P. 466 50% 501 F.B.P. 669 Flash point -a 215 Gravity 0.84

. Mol. Wt, ca 200 U. sulf. res. percent 98+ Percent aromatics 0 Percent naphthenes 60 Percent paraflins 40 'The esters of the oxidized white oils can also be utilized. These esters can be prepared by esterifying with an added alcohol such as butyl alcohol in the presence of an acid catalyst, e.g. acid resins, sulfuric or an aromatic sulfonic' acid catalyst, in an amount of from .01 to 1' wt. percent and using an aromatic solvent such as benzene, toluene, etc. "Thenatural"-esters can also be used. This term connotes'esters prepared by the interaction of alcohols and acids contained in the oxidized "180 C. They result from the in situ reaction of alcoholic (--'OH) oxidation products with acidic (--COOH) oxidation products. For purposes of testing these natural esters as defoliants, they were first extracted from the total mixture ofoxidized- XCT white oiloxidation tions should lie within the following limits:

products. This was done by adding equal parts'of petr. ether and ammoniacal isopropanol (50/50 concentrated ,synthetic oils are. also satisfactory. In general, the oils should-be. of a relatively bland, non-toxic nature since any composition which would kill the plant outright could not promote the development of the abscission layers which is necessary to successful defoliation. In

order to avoid objectionable staining of the cotton fibers,

oils with only a fairly light color should be used. These oils typically have a boiling point in the range of 250 to 550 -l=.,a vic'osity in the range of 30 r0200 SSU/ 100 F. and the petroleumoils are predominantly at least 50 wt. percent to wt. percent parafiinic or naphthenic.

The synthetic oxygenated fraction known as" Oxo bottoms can also be utilized, and are intended tobe connoted by the term mineral spray oil. Thepreparation and the characterof these Oxo bottoms are described in detail It can also be applied to edible Blends of the mineral spray clude by way of example, by trade name and chemical description as follows: Igepol CO-630, alkyl aryl polyoxyethylene glycol ether; Acto, petroleum sulfonate; Nonisol 210, polyethylene glycol oleate; Tween 21, polyoxyalkylene derivative of sorbitan monolaurate; Triton Emulsifier would be added as be- X45, alkylated aryl polyether alcohol; Mulsor 3CW, long V I chain fatty acid ester containing multiple ether linkages;

and a petroleum sulfonate modified with a minor amount of a non-ionic emulsifier. Blendscan be utilized.

The compositions of this invention are thus conveniently made up in the forms of emulsion concentrates containing 5 to 50 wt. percent of the active ingredient,

to 90 wt. percent of the mineral spray oil, and 1 to 10 wt. percent of the emulsifier. These concentrates can then be diluted in the field with water so that the emulsion concentrate constitutes from 10 to wt. percent of V the total aqueous emulsion formulation. The active ingredient is contained as an emulsion concentrate which is emulsified with water. As stated previously, the concentrations as well as the components themselves are important to secure the desired activity. a

The aqueous emulsion is applied to the plants at a rate of 5 to 40 gallons per acre, preferably 5 to 20 gallons' per acre. The lower figures are employed in airplane spraying and the upper ones for ground spray equipment. plant, e.g., it is most effectively applied to cotton plants when the latter have matured as when 40% of the cotton bolls have opened. Ten days to two weeks is all that is normally required to secure the maximum defoliation. No adverse effect is noted on the crops where the composition of this invention is applied to cotton. dry beans, soybeans, and flax. V p

The following examples illustrate this invention and indicate test results obtained with the compositions of this invention emulsified with water as well as the preparation of the active ingredients.

EXAMPLE 1 Preparation of oxidized Marcol JX Marcel IX was oxidized as taught until it contained about 5.1 Wt. percent 0 The details areas follows: 2500 cc. Marcol IX was charged to a 4 liter 3-necked flask fitted with a stirrer, thermometer, condenser and water recovery trap. Oxygen was passed through the white oil at a rate of 40 cc. per minute while stirring and bringing the temperature of the pot up to 170-180 C. The temperature in the reaction flask was held at this level until 250 cc. of water had been collected in the water removal trap.

EXAMPLE 2 Preparation of n-butyl ester of oxidized XCT white oil Esterification apparatus (fitted with thermometer, condenser, stirrer and water removal trap) was charged with 2075 g. of oxidized XCT white oil (having 135-200" ,C. b. pt., acid No. 85 mgms. KOH/gm.). To this was added 400 cc. n-butyl alcohol, 1 gm. toluene sulfonic acid catalyst and toluene'as H O entrainer. This mixture was stirred and refluxed until 76 cc. of H 0 was removed. The resulting product was water washed, dried The time of application varies with the- 4 over Na SO and stripped under vacuum to remove toluene. After stripping, the remaining product was fractionated at 1 mm. pressure. The fraction boiling at -152 C. was tested as a defoliant. Inspections of 115-152 fractions are as follows:

Combining wt 6260.

Acid N0 9.0.

Sap No 180.0.

Br No l6.

1 double bond/ 1000 comb. wt.

V./ 100 F 80 SSU.

V./210 F 36 SSU.

Pour pt 60 F.

Flash pt 345 F.

Percent 0 12%, est. by difierence from C+H.

EXAMPLE 3 Preparation of natural esters of oxidized XCT white oil Oxidized XCT white oil (b. pt. l35-225 C.) was ,taken up in equal quantity of petroleum ether. To this was added equal portion of ammoniacal isopropanol (50% concentrated aqueous NH;,/ 50% IPOH). The IPOH layer was drawn oif in a separatory funnel, thus removing acidic oxidation products as NH salts. The petroleum ether layer was re-extracted with NH /IPOH, then washed with H O till neutral. Petroleum ether was stripped, the residue representing natura esters of oxidized XCT white oil. Inspections:

The following data show the relationship of natural ester boiling range to combining wt. and acid No. of

XCT white oil natural esters. 15,000 to 300 combining wt. is Preferred.

Bolling Range Comb. Wt. Acid No.

EXAMPLE 4 A detailed study of a typical oxidation of a typical white oil follows.

2500 cc. of XCT white oil blown with air (ca. 40 cc./ min.) at ISO- C. H O recovered and oil sample analyzed as each 50 cc. of water is collected:

The various active ingredients were applied in the form V of aqueous emulsions to cotton plants at the Delta Branch Experiment Station, Stoneville, Mississippi. Each formulation was applied to four hills, each hill containing from 1 to 3 plants; WS-1449 is a 50/50 blend of'Bayol D, a

5 V petroleum white oil with Mentor 28, a conventionally re fined paraflin oil having an unsulfonatable residue of 85-90%. The blend viscosity is 45SSU/ 100 F. The application rate was as indicated. The result were tabuin situ reaction of the alcohols and the acids contained in the oxidized white oil.

6. A defoliant aqueous emulsion concentrate composition comprising from 2 to 50 wt. percent of an active ingredient selected from the group consisting of oxidized lated 10 days to 2 weeks after application. The results 5 V were as follows: white 0115 having a peroxlde number in the range of 10 Formulation Esti- Applied Appllc. mated As- Rate Percent Active Ingredient, Wt. Percent Carrier, Wt. Emulsifier, Wt. (Gal/A) De;

Percent Percent foliation Oxidized MarcolJX, 10% WS-1449, 85%- 35,333. }26%em 1 2 65 Oxidized MarcolJX,20% ws-nio, 75%..- {k gffggfi i }25%emu.ls 20 e n-p l ltgl e ter of oxidized xo'r, va s-1449, 85%--- {flgg ggigg 3 }2 m l 2 741-7 Natural esters of oxidized xo'r, WS-1449, 85%..- i i gg iggj }2s% emuls- 20 10-75 Mulsor sow, a% None WS1449, 87%-.. Auto 630 2% 25% emu1s-- 40 The defoliation figure represents the leaf drop/total original leaves times 100. 65 to 70% defoliation is the minimum required for an effective defoliant. The figures presented above demonstrate that about 65% and usually greater defoliation was obtained with compositions of this invention as constrasted to 20% for the control. Greater activity can, of course, be obtained by utilizing higher concentrations of the active materials within the stipulated ranges.

The utilization of the compositions of this invention represents extremely large labor savings and lower growing costs.

It is to be understood that this invention is not limited to the specific examples which have been offered merely as illustrations, and that modifications may be made without departing from the spirit of this invention.

What is claimed is:

1. A method of defoliating a plant which comprises applying to said plantan aqueous emulsion comprising an organic composite of from 5 to 50 wt. percent of an active ingredient selected from the group consisting of oxidized white oils having a peroxide number in the range of 10 to 100 and an oxygen content in the range of 1 to 20 wt. percent and their esters, the starting white oils being naphthenic, aromatic-free oils having the following physical properties:

Molecular weight 200-500 Specific gravity, 60/60 F. 0.75-0.90 Saybolt viscosity 100 F. 50-200 Unsulfonated residue percent..- 95-100 Pour point F 0 from 40 to 90 wt. percent of a relatively non-toxic horticultural mineral spray oil, from 1 to 10 wt. percent of an oil soluble emulsifying agent, said organic composite constituting from 10 to 50 wt. percent of the total aqueous emulsion said emulsion being applied at a rate of 5 to 40 gallons per acre.

2. The method of claim 1 in which the plant being treated is cotton.

3. The method of claim 1 in which the active ingredient is an oxidized light white mineral oil.

4. The method of claim 1 in which the active ingredients are the butyl esters of an oxidized white oil.

5. The method of claim 1 in which the active ingredients are the esters of an oxidized white oil formed by the to 100 and an oxygen content in the range of 1 to 20 wt. percent and their esters, the starting white oils being naphthenic, aromatic-free oils having the following physical properties:

Molecular weight 200-500 Specific gravity, 60/60 F. 075-090 Saybolt viscosity 100 F. 50-200 Unsulfonated residue percent 95-100 Pour point F 0 from 40 to wt. percent of a relatively non-toxic horticultural mineral spray oil, and from 1 to 10 Wt. percent of an oil soluble emulsifying agent.

7. The composition of claim 6 in which the active ingredient is an oxidized light white mineral oil.

8. The composition of claim 6 in which the active ingredients are the butyl esters of an oxidized white oil.

9. The composition of claim 6 in whichsthe active ingredients are the esters of an oxidized white oil formed by the insitu reaction of the alcohols and the acids contained in the oxidized White oil.

' 10. A defoliant aqueous emulsion concentrate comprising 40 to 90 wt. percent of a relatively non-toxic horticultural mineral spray oil, 1 to 10 wt. percent of an oil soluble emulsifying agent, and 5 to 50 Wt. percent of an active defoliating agent prepared by the non-catalytic oxygen blowing of a naphthenic, aromatic-free, petroleum white oil, having the following physical properties:

Molecular weight -l- 200-500 Specific gravity, 60/60 F. 0.75-0.90 Saybolt viscosity 100 F. 50-200 Unsulfonated residue percent -100 Pour point F 0 References Cited in the file of this patent UNITED STATES PATENTS 1,707,468 Volck Apr. 2, 1929 1,914,903 Volck June 20, 1933 2,123,457 Wilson July 12, 1938 2,710,794 Barnsley June 14, 1955 2,746,853 1956 Yowell May 22, 

1. A METHOD OF DEFOLIATING A PLANT WHICH COMPRISES APPLYING TO SAID PLANT AN AQUEOUS EMULSION COMPRISING AN ORGANIC COMPOSITE OF FROM 5 TO 50 WT. PERCENT OF AN ACTIVE INGREDIENT SELECTED FROM THE GROUP CONSISTING OF OXIDIZED WHITE OILS HAVING A PEROXIDE NUMBER IN THE RANGE OF 10 TO 100 AND AN OXYGEN CONTENT IN THE RANGE OF 1 TO 20 WT. PERCENT AND THEIR ESTERS, THE STARTING WHITE OILS BEING NAPHTHENIC, AROMATIC-FREE OILS HAVING THE FOLLOWING PHYSICAL PROPERTIES: POUR POINT *F FROM 40 TO 90 WT. PERCENT OF A RELATIVELY NON-TOXIC HORTICULTURAL MINERAL SPRAY OIL, FROM 1 TO 10 WT. PERCENT OF AN OIL SOLUBLE EMULSIFYING AGENT, SAID ORGANIC COMPOSITE CONSTITUTING FROM 10 TO 50 WT. PERCENT OF THE TOTAL AQUEOUS EMULSION SAID EMULSION BEING APPLIED AT A RATE OF 5 TO 40 GALLONS PER ACRE. 